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For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
---------------------------------------------------

Stagecraft Digest, Issue #474

 1. grey list
    by Judy <kupfer [at] post.tau.ac.il>
 2. Re: Show record photography advice
    by "C. Dopher" <brooklyn [at] dopher.com>
 3. Re: Show record photography advice
    by Steve Larson <tiptd [at] theatreinthepark.com>
 4. Re: Show record photography advice
    by "Jim at TheatreWireless.com" <stagecraft [at] theatrewireless.com>
 5. digital photos
    by "RICHARD FINKELSTEIN" <rfinkels [at] msn.com>
 6. Re: RGB lighting idea - ruminations (long)
    by Jerry Durand <jdurand [at] interstellar.com>
 7. strange light control devices
    by Jerry Durand <jdurand [at] interstellar.com>
 8. Re: RGB lighting idea
    by "C. Dopher" <brooklyn [at] dopher.com>
 9. Re: Makita batteries
    by "Paul Guncheon" <paul.guncheon [at] verizon.net>
10. Re: Eidophor (was RGB lighting idea)
    by "richard j. archer" <rja10 [at] cornell.edu>
11. RGB lighting
    by "Chris Warner" <bearz2 [at] cox.net>
12. Re: RGB lighting
    by "Jerry Durand" <jdurand [at] interstellar.com>
13. Re: RGB lighting idea
    by Stuart Wheaton <sdwheaton [at] fuse.net>
14. Re: Makita batteries
    by Dale Farmer <dale [at] cybercom.net>

*** Please update the subject line of your reply to use the subject
*** line of the message you are replying to! Please only reply to
*** one message subject in each reply.

----------------------------------------------------------------------

Message-ID: <42EB6E09.2040906 [at] post.tau.ac.il>
Date: Sat, 30 Jul 2005 14:09:45 +0200
From: Judy <kupfer [at] post.tau.ac.il>
Subject: grey list

Thank you Pat! I tried out a few things when reading this:

> This is not a problem in single messages, but it sounds as if your 
> newsreader sees one of those triggers in the digest and interprets 
> everything below it - including other people's messages - as part of a 
> .sig file. If I'm correct, then you'll see everything below this 
> message in light grey.
> -- 
>
When reading it at home through Thunderbird, the next few lines of the 
next message were light grey, but then the rest of the digest was 
normal. However then I went to read it off the web, at the webmail site, 
and indeed the whole thing was gray! After that I forwarded it to my 
Yahoo account, and nothing at all was gray.  So I'm really happy to know 
a little more about that.


------------------------------

Date:	Sat, 30 Jul 2005 07:40:10 -0400
Subject: Re: Show record photography advice
From:	"C. Dopher" <brooklyn [at] dopher.com>
Message-ID: <BF10DF5A.1BC06%brooklyn [at] dopher.com>
In-Reply-To: <20050730011427.KUTX19894.tomts20-srv.bellnexxia.net [at] p3m866>

On 7/29/05 9:14 PM, "Jim at TheatreWireless.com"
<stagecraft [at] theatrewireless.com> wrote:

>> I have objections to this.  I've seen several designers do
>> this and the results ALWAYS look photoshopped.  I see this
>> and begin to doubt that the designer has confidence in
>> his/her abilities or is frustrated that his/her lighting (or
>> scenic design) never comes out the way they intended and
>> -mostly- that they're not satisfied with the product they're
>> putting in front of audiences.
> 
> In the digital domain, I don't entirely agree with you.
> 
> The dynamic range of digital cameras remains inferior to film; merging
> multiple images taken in rapid succession and nearly identical except for
> exposure settings, simulates the wider range of film.  Done right, the
> composite image will have the tonal and dynamic depth we expect from a good
> quality photograph, and replicate reasonably what we see with our eyes.
> Many of the best lighting designs demand this treatment when recorded with a
> CCD, otherwise detail in light areas will be lost in digital 1s, and detail
> in dark areas will be lost in digital 0s.
> 
> Bracketing is necessary sometimes.  In my opionion, anyway.
> 
> Jim
> 
> 

But you're taking me slightly out of context.  What Steve SAID was: "I'm not
adverse to cutting and pasting together the best of several shots to get the
look I'm after."  That didn't sound like the merging of bracketed photos to
me.  It sounded like pulling the cyc from this shot, the set lighting from
that show, and the lit actors from another shot, all lit fairly differently.

Steve, would you like to clarify?

Cris Dopher


------------------------------

Date: Sat, 30 Jul 2005 09:02:08 -0400
Subject: Re: Show record photography advice
From: Steve Larson <tiptd [at] theatreinthepark.com>
Message-ID: <BF10F290.6D0E%tiptd [at] theatreinthepark.com>
In-Reply-To: <list-23953587 [at] prxy.net>

Gladly.  Actress in white dress is standing
against a darker background.  It is virtually
impossible to get detail on both at the same
time.  The dress is going to bloom.  I'm good
enough at Photoshop that I can do it and you
won't tell.  I generally don't do a lot of this,
but can and will where necessary.

I'm far enough into my career that the portfolio
doesn't matter any more.  I've run out of room
to store things anyway. I shoot theatre photos
for our archives.  I shoot outside the theatre
to sell and display.

The range of digital cameras has expanded to
12.4 megapixel with the Nikon D2X and over 16 megapixel
with one of the new Canon's.  That's as good
as film, isn't it?  Anyone have any comparisons of megapixels
to ISO.  I'm sure one of you has that info available.

Neither one of us is so good at lighting that
we can light the scene perfectly where a camera
using digital or film can take the perfect picture.

We keep trying though.

Steve

> From:  "C. Dopher" <brooklyn [at] dopher.com>

> Steve, would you like to clarify?
> 
> Cris Dopher
> 
> 
> 


------------------------------

From: "Jim at TheatreWireless.com" <stagecraft [at] theatrewireless.com>
Subject: RE: Show record photography advice
Date: Sat, 30 Jul 2005 09:39:22 -0400
In-Reply-To: <list-23954223 [at] prxy.net>
Message-Id: <20050730133928.NDOV19894.tomts20-srv.bellnexxia.net [at] p3m866>

> The range of digital cameras has expanded to
> 12.4 megapixel with the Nikon D2X and over 16 megapixel with 
> one of the new Canon's.  That's as good as film, isn't it?  
> Anyone have any comparisons of megapixels to ISO.  I'm sure 
> one of you has that info available.

The number of pixels is a separate specification from the dynamic range.
Dynamic range is related to the number of bits used to convert the CCD data
to numbers.  The more bits, the more range, provided the CCD is good enough
to produce the data in the first place.  

Ben Kreunen has an interesting web site about some of this stuff, where he's
done some of his own tests:
http://www.path.unimelb.edu.au/~bernardk/tutorials/360/technical/hdri/

I'm sure Google would turn up more about it as well.

Jim



------------------------------

Message-ID: <BAY106-F13018B9B7962F36AADA87C7C10 [at] phx.gbl>
From: "RICHARD FINKELSTEIN" <rfinkels [at] msn.com>
Subject: digital photos
Date: Sat, 30 Jul 2005 10:26:00 -0400

QUOTING CHRIS DOPHER...

>>  I'm not adverse to cutting and pasting
>>together the best of several shots to get the look I'm after.

>I have objections to this.  I've seen several designers do this and the
>results ALWAYS look photoshopped.  I see this and begin to doubt that the
>designer has confidence in his/her abilities or is frustrated that his/her
>lighting (or scenic design) never comes out the way they intended and
->mostly- that they're not satisfied with the product they're putting in
>front of audiences.

>Become a better photographer, record your show AS IT STANDS, and be done
>with it.  Man up to what you put on stage.

>Cris Dopher, LD

Although I agree that this approach is not always done well this and similar 
techniques have long ago been "vindicated" in other transfers between media. 
A case in point came from the Long Beach USITT session with multiple Emmie 
LD Bill Klages. He has had to totally relight the Broadway shows he has 
transferred to video so that they can look like they were NOT relit!  As 
others have stated, the sensitivity curves of either film, video, or various 
digital capture technologies differ substantially from each other. The way 
to NOT make a picture look like it did in the theatre is to take no action!

Here are a few examples from my own work also showing other reasons to adopt 
these techniques.

Most of the photos I took of this production of The Mystery of Edwin Drood
http://www.rfdesigns.org/drood.htm
used multiple exposures per shot. Here I was set designer and not lighting 
designer. The first photo demonstrates most clearly the need to use the 
multiple exposures. The LD did the traditional and proper thing of keeping 
the bulk of the light on the performers.  In house this looked great! The 
white drop sang out and the actors in front looked great in front of the 
drop.  In ALL of my 100+ exposures of these in-one scenes, however, either 
the top half of the drop went totally black when the performers looked 
great, or the performers and the bottom half of the drop went to white out 
when the top of the drop  was visible.

It would be foolish to say that the 1/2 drop visibility was "true to life" 
when this was simply NOT the case. All human eyes in the audience were able 
to see the drop as a whole perfectly as well as the performers perfectly.

The second factor here is that as a set designer I needed the scenery to be 
seen in the shots. Again audience members had no problem seeing the scenery, 
but the contrast ratios of stage lighting are just too great for the 
lattitude of either film or digital cameras.

Another victim of this in these shots were the portals. They looked 
wonderful live but went totally dark in otherwise properly exposed photos, 
so combining shots exposed for each actually rendered images that simulate 
the live experience quite accurately.

Yet as a musical, the contrast ratios here were not too extreme.  Compare 
the problems here to a show with a darker theme, Chaucer in Rome, where I 
did both scenery and lighting:

http://www.rfdesigns.org/chaucer.htm

Here the third and sixth shot combined multiple exposures.  The contrast 
ratios on stage were over 100:1.  In single exposures it would be impossible 
to see any detail at all in the characters, yet audiences had no problem at 
all seeing the faces of the performer even though they were in extreme 
shadow. The eye is simply that remarkable. Again the one shot approach would 
have been the way to DENY how the show really looked.

Now an extreme example that will make some of you mad, but what the hey!

Probably my largest show I ever designed was a new musical with a score of 
big-name stars called All-Time Good-Time Knickerbocker Follies.  I served as 
scenic designer and the show was lit by the late Richard Nelson, immediately 
after his Tony-Award design of Into the Woods.
As you can see from the shots at:   http://www.rfdesigns.org/knick.htm
(slides here as this was LONG before digital)  The show featured some highly 
sculptural golden portals.

Richard Nelson put no light whatsoever on these most important scenic units. 
He didn't have to as the reflective multi-planar surfaces caught the spill 
light beautifully. As they were reflective, had he put direct lighting on 
them they would have blinded the audience. As in the case of Drood, the 
light at the top of the drops was also far far far lower in level than the 
lighting at the performer level of the stage. (the third photo on the page 
comes closest to what FILM registered. Note how much detail is already lost 
by the tops of the drops, detail seen perfectly well by the humans in the 
audience).

In my slides, the portals, that to the audience made for at least half the 
stage picture, totally totally disappeared. GONE! To say that the show 
looked like the photos would be totally and absolutely WRONG!  I felt so sad 
that one of my favorite shows might have been lost forever in 
documentation....till the digital age came to the rescue, albeit here 
through extreme measures.

As I said earlier there was no light at all focused on the portals (though 
they looked GREAT to the audience), so no amount of bracketing was able to 
get a single shot showing any detail at all of these.

So what you are seeing in the first shot on the page is actually a composite 
digital image of the stage itself in the center with the portals from the 
model added in. Of course the world of film has been doing "model shots" for 
over a century so there is nothing new here but this is indeed a strategy 
employed to rescue documentation that would have otherwise been totally 
lost.

Another area where the multi-exposure approach seems to me to be mandated is 
in many cases where projection designs are used. Here too a projected image 
that may look bright to an audience may in light meter terms be many degrees 
dimmer than the light on the performer. In these circumstances there is no 
way to make a single photo look like what the audience perceived.  Anyone 
that has taken slides of performances featuring pretty cycs know this issue 
well. So often the cycs look bright to your eye in the theatre only to 
TOTALLY disappear in photos. Would it be right to say that the photo is 
accurate, that the sky was "really" black and that the audience was mistaken 
for having seen the sky as blue? I think not!

RichardF



------------------------------

Message-Id: <6.2.3.4.0.20050730094818.029e2520 [at] 192.168.0.13>
Date: Sat, 30 Jul 2005 09:53:16 -0700
From: Jerry Durand <jdurand [at] interstellar.com>
Subject: Re: RGB lighting idea - ruminations (long)
In-Reply-To: <list-23934547 [at] prxy.net>
References: <3CF87682970858499CA56707FB1F092B0A920A [at] wscc-s-003000.westshore.edu>
 <list-23930022 [at] prxy.net>
 <list-23934547 [at] prxy.net>

At 10:08 PM 7/28/2005, you wrote:
>I don't know about "unique" - the idea is not original. Some early color
>televisions used the spinning RGB wheel - there was even a construction
>project in one of the electronics magazines. I think the early color
>cameras also used the wheel with one B&W vidicon tube. I doubt if anyone
>could get a patent on that part of the idea.

But this is for a spot/flood light.  Different use (until we just use 
a high-power DLP system to light the stage).


>Now, timed pulses through a spinning dicro tri-wheel, that has possibilities.

True.

Interesting thing, I saw the DLP wheels in smalltimes Magazine, all 
about nano-tech stuff.  I don't know what about a color wheel is 
nano-tech, unless they're using quantum dots for the color filter.

Now there's one, a color filter that changes color based on the DC 
voltage...just a sheet of quantum dots.  It's coming...


BTW, on the patent idea...  Since I first mentioned it here and 
several people have come in with ideas, if someone is any good at 
patent stuff, I'd be willing to help get this set up with the 
proceeds going to USITT (with a small fund to keep the Stagecraft 
mailing list running).  Any thoughts?


----------
Jerry Durand
Durand Interstellar, Inc.
219 Oak Wood Way
Los Gatos, California 95032-2523 USA
tel:  +1 408 356-3886, USA toll free:  1 866 356-3886
web:  www.interstellar.com




------------------------------

Message-Id: <6.2.3.4.0.20050730104955.029a2078 [at] 192.168.0.13>
Date: Sat, 30 Jul 2005 10:55:44 -0700
From: Jerry Durand <jdurand [at] interstellar.com>
Subject: strange light control devices

Another thought just occurred to me while reading about PBG crystals 
(think of a tiny filter that can be turned on and off) at 
http://www.external.ameslab.gov/final/News/2005rel/tallcrystals.htm

Anyway, how about this:

Take an optically flat, reflective, conductive surface (first surface 
metal mirror);

Coat it with a THIN layer of a clear, non-conductive, compressible compound;

Coat that with an even thinner layer of a conductor (like used on LCDs).

Now, bounce light off this, you have a dichroic filter.

Apply a DC voltage between the two conductors and the top layer will 
be attracted to the mirror, compressing the stuff in the middle...the 
color of the filter just changed.

The center compressible stuff could be standoffs, too.  Think tiny 
springs.  Bucky tubes?

-- 
Jerry Durand
Durand Interstellar, Inc.
219 Oak Wood Way
Los Gatos, California 95032-2523 USA
tel:  +1 408 356-3886, USA toll free:  1 866 356-3886
web:  www.interstellar.com



------------------------------

Date:	Sat, 30 Jul 2005 14:04:58 -0400
Subject: Re: RGB lighting idea
From:	"C. Dopher" <brooklyn [at] dopher.com>
Message-ID: <BF11398A.1BC09%brooklyn [at] dopher.com>
In-Reply-To: <3.0.6.32.20050729192023.00796820 [at] mail.interlog.com>

On 7/29/05 7:20 PM, "Villem Teder" <vteder [at] interlog.com> wrote:


> On the other hand, a few years ago, some one posted an abstract claiming to
> be either a Varilite patent, or patent pending, on the use of LCD elemants
> as shutters and/or gobos in lighting fixtures. As I read it, I couldn't
> help but think that I was reading a description of how LCD projectors in
> general worked!

Yes, VL was working on digital gobos.  May still be, FAIK.  Having a drop-in
digital gobo for Source 4, controllable from software running on any given
platform, and triggered by a MIDI or DMX signal... Now that's be the
squirrel's nuts right there!

Cris Dopher


------------------------------

Date: Sat, 30 Jul 2005 08:50:56 -1000
From: "Paul Guncheon" <paul.guncheon [at] verizon.net>
Subject: Re: Makita batteries
Message-id: <002b01c59537$9f695ef0$c6354104 [at] yourxhtr8hvc4p>
References: <list-23952829 [at] prxy.net>

<<The usual battery pack problems I've run into relate to using the wrong
charger, or someone screwing with the charger to make it charge faster.  One
time the issue was that there was a rack of battery chargers in a locking
cabinet without any ventilation.  At the end of the day they were loaded up
with variously used up batteries and locked up.  Heat buildup from charging
accelerated aging of the batteries.>>

Sorry, but this is not operator error...

1235 F
12v NIMH
No special charger.  Instructions (minimal) are to deplete and recharge 3
times in succession the first three time of use.

Batteries work great for about the first 10 recharges then rapidly lose
their amp hour rating.  I have some that I would rate at around 1.5 ah.

Esssentially, they're carp (spell check approved).

I now make it a rule to NEVER charge batteries on a generator. Period.  I've
lost 4 - DeWalt 18v batts and 4 - 12v Makita batts to various generators.

As you all can see, I am an exceptionally fast learner.

<<
> When you mention a generator, do you mean a typical 120V/60Hz gas genny?
If
> it outputs a sine-wave anywhere near spec it probably isn't related your
> problem.>>

They were tow plants.. not sure how big, but used to provide power for movie
locations.. usually diesel.  I was told the last one that killed my
batteries did not have "crystal synch", (whatever that means).  The now
ruined batteries when inserted in a charger connected to wall power will
enter the charging phase, and be "completely charged" (green light) in
around 30 minutes... and have pretty much no life at all.

Laters,

Paul

"I don't believe in the Heimlich maneuver", Tom struck back.



------------------------------

Message-Id: <p05210600bf1182de9d12 [at] [132.236.252.58]>
In-Reply-To: <list-23946963 [at] prxy.net>
References: <list-23946963 [at] prxy.net>
Date: Sat, 30 Jul 2005 14:27:55 -0500
From: "richard j. archer" <rja10 [at] cornell.edu>
Subject: Re: Eidophor (was RGB lighting idea)

>Villem Teder said



>
>I think Jerry is vaguely describing the Eidophor, the original large screen
>video projection system.


My 7/26 reference to the Opera Company of Boston's 1969-70 production 
of Good Soldier Schweik could have mentioned that this production 
used a rather large (but very high tech at the time) black and white 
Eidophor for dream sequences and for live projection of the opera as 
it was happening. As mentioned, the production was in the Boston 
College hockey rink and later in the MIT arena so it was sort of two 
sided but not really in the round.  The screen was center stage above 
the actors and the orchestra was in a platform built above the screen 
(I cannot remember how they convinced the musicians to get up there 
so don't ask.  Maybe someone else on the list saw this production?)

Dick A
TD, Cornell U


------------------------------

Message-ID: <009301c5953e$3832a000$6401a8c0 [at] chris>
From: "Chris Warner" <bearz2 [at] cox.net>
Subject: RGB lighting
Date: Sat, 30 Jul 2005 12:38:11 -0700

Anybody know of a source from DLP or other LCD chips?  TI's website doesn't
have a single blip on it about sources.  This is an interesting project idea
that I think I can put together, IF I can find the graphic chips.

Thanks in advance
Chris Warner



-- 
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.338 / Virus Database: 267.9.7/60 - Release Date: 7/28/2005


------------------------------

Message-ID: <1822.69.3.26.83.1122756884.squirrel [at] www.interstellar.com>
In-Reply-To: <list-23958135 [at] prxy.net>
References: <list-23958135 [at] prxy.net>
Date: Sat, 30 Jul 2005 13:54:44 -0700 (PDT)
Subject: Re: RGB lighting
From: "Jerry Durand" <jdurand [at] interstellar.com>

On Sat, July 30, 2005 12:38 pm, Chris Warner wrote:
> Anybody know of a source from DLP or other LCD chips?  TI's website
> doesn't
> have a single blip on it about sources.  This is an interesting project
> idea
> that I think I can put together, IF I can find the graphic chips.

I'm a TI Third Party, I'll check with my factory rep...




------------------------------

Message-ID: <42EC278E.8010905 [at] fuse.net>
Date: Sat, 30 Jul 2005 21:21:18 -0400
From: Stuart Wheaton <sdwheaton [at] fuse.net>
Subject: Re: RGB lighting idea
References: <list-23920973 [at] prxy.net> <list-23921495 [at] prxy.net> <list-23922911 [at] prxy.net> <list-23923772 [at] prxy.net> <list-23926745 [at] prxy.net>
In-Reply-To: <list-23926745 [at] prxy.net>

Jerry Durand wrote:

> 
> A predecessor to the DLP was used by NORAD.  Take a metal mirror in a 
> vacuum, spray a mist of oil on it and clean off pixels with an electron 
> beam.  Repeat.  With an arc light and a few mirrors, you have slow 
> animations of missiles coming in from the USSR up on the wall.

Was this the technology behind GE's Telaria series of Video 
projectors?   I worked with a few of those back in the 80's 
and I recall some kind of glass rotating in a oil as being 
the reason they were so sensitve to shock and tilting.


Stuart




------------------------------

Message-ID: <42EC62D8.4B5BF2D2 [at] cybercom.net>
Date: Sun, 31 Jul 2005 01:34:16 -0400
From: Dale Farmer <dale [at] cybercom.net>
Organization: The  fuzz in the back of the fridge. 
Subject: Re: Makita batteries
References: <list-23952829 [at] prxy.net> <list-23957510 [at] prxy.net>



Paul Guncheon wrote:

> For info, archives & UNSUBSCRIBE, see <http://stagecraft.theprices.net/>
> ---------------------------------------------------
>
> <<The usual battery pack problems I've run into relate to using the wrong
> charger, or someone screwing with the charger to make it charge faster.  One
> time the issue was that there was a rack of battery chargers in a locking
> cabinet without any ventilation.  At the end of the day they were loaded up
> with variously used up batteries and locked up.  Heat buildup from charging
> accelerated aging of the batteries.>>
>
> Sorry, but this is not operator error...
>
> 1235 F
> 12v NIMH
> No special charger.  Instructions (minimal) are to deplete and recharge 3
> times in succession the first three time of use.
>
> Batteries work great for about the first 10 recharges then rapidly lose
> their amp hour rating.  I have some that I would rate at around 1.5 ah.
>
> Esssentially, they're carp (spell check approved).
>

    That sounds like you got a bad batch of batteries in.   Call makita
tech support and relate your problems to them.  They should figure
out the bad lot of batteries and replace them with good ones.   Did
you buy this whole batch at once, or all from the same supplier over
a short period of time? The only other possibility is that one of your
tools has something broken about it that is killing the batteries.
( High rate current draw from these types of batteries will release a
*lot* of heat in a very short time, which will kill the battery too. If
you wanna see some fireworks, put a dead short across the terminals.
The thing has a decent chance of exploding. )

>
> I now make it a rule to NEVER charge batteries on a generator. Period.  I've
> lost 4 - DeWalt 18v batts and 4 - 12v Makita batts to various generators.
>
> As you all can see, I am an exceptionally fast learner.
>
> <<
> > When you mention a generator, do you mean a typical 120V/60Hz gas genny?
> If
> > it outputs a sine-wave anywhere near spec it probably isn't related your
> > problem.>>
>
> They were tow plants.. not sure how big, but used to provide power for movie
> locations.. usually diesel.  I was told the last one that killed my
> batteries did not have "crystal synch", (whatever that means).  The now
> ruined batteries when inserted in a charger connected to wall power will
> enter the charging phase, and be "completely charged" (green light) in
> around 30 minutes... and have pretty much no life at all.

    Larger diesel generators like you describe should not have any issues
with charging batteries.   Crystal synch isn't a term I've heard of before,
but is sounds like one of the systems that is used to run multiple generators
all feeding a common electrical system.  If one is out of synchronization
with the other, it actually starts driving the generator of the one that is
lagging behind as a motor.  This is bad.  Not only does it waste a lot of
fuel, but it can, in severe cases, melt or ignite the lagging generator if
not corrected.  Generators designed for this mode of operation are
a bit more expensive.

    --Dale



------------------------------

End of Stagecraft Digest #474
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